This invention relates stringed musical instruments, such as guitars, and methods for making such stringed instruments.
Stringed instruments traditionally have been constructed of wood, but also have been fabricated from plastics, molded composite materials, and combinations of such materials. As shown in FIG. 1, a conventional stringed instrument typically includes a body 10, a neck 12, a head 14 (sometimes called a “headstock”), a soundboard 16, a fingerboard 18 (sometimes called a “fretboard”), strings 20, a bridge 22 and a sound hole 24. In acoustic stringed instruments the interior of body 10 is hollow, and forms a resonant cavity, often called a “sound chamber.” In acoustic stringed instruments, the vibration of strings 20 is transmitted through bridge 22 to the body via soundboard 16. In turn, the vibration of soundboard 16 vibrates air inside the sound chamber, and produces the sound that is projected from sound hole 24.
In many conventional stringed instruments, the various components are constructed separately, and then joined to form a finished instrument. Because the structural integrity of a stringed instrument affects the tonal quality and sound output of the instrument, stringed instruments made from separately joined parts experience some loss in sound quality. In addition, in many conventional stringed instruments, the neck 12 and head 14 are made of solid material, which decreases the volume and tonal range of the instrument because the added weight dampens resonance. Generally speaking, a lighter instrument is better than a heavier one as long as stiffness is substantially similar. The most expensive and resonant guitars typically are very light and also very stiff relative to their weight. Further, solid neck and head components reduce the “sustain” of the instrument—that is, the length of time that the strings “ring” when played.
Small-bodied stringed instruments, such as small-bodied acoustic guitars designed for travel, are particularly susceptible to sound degradation attributable to design and manufacturing considerations. In particular, small-bodied stringed instruments typically have a relatively small sound chamber, and thus have reduced volume and tonal range compared with that of normal-sized stringed instruments. The sound degradation for small-bodied stringed instruments is further exacerbated by use of a solid neck. In addition, a common problem with small-bodied acoustic guitars is that the solid neck is heavier than the hollow body, which requires the user to awkwardly elevate the neck to play the instrument.
Some designers and manufacturers have sought to improve sound quality or structural integrity of stringed instruments by providing a hollow neck that forms an enclosed passage that communicates with the sound chamber and one or more sound holes located at the headstock. Such “expanded sound chamber” designs benefit from the continuous hollow sound chamber between the body and neck. However, such previously known designs typically are fabricated from numerous separate components that must be attached to form the finished instrument. Thus, the improvement in sound quality resulting from the expanded sound chamber is offset by the lack of structural integrity and resulting degradation in sound quality attributable to construction from separate parts.
As an alternative approach, some designers and manufacturers have sought to improve sound quality or structural integrity of stringed instruments by fabricating instruments using so-called “one-piece” designs that reduce the number of separate components that must be joined to form the finished instrument. Although such “unitary” stringed instruments offer some improvements over conventional designs, they each suffer from significant drawbacks that negatively impact sound quality and/or manufacturability.
Indeed, some form of unitary stringed instruments appeared in the late 19th century. Such instruments were typically constructed of wood, were extremely time-consuming to manufacture, and were very fragile. More recently, guitar designers and manufacturers have created molded unitary stringed instruments using composite and/or injection-molding techniques. However, such molded unitary stringed instruments typically include numerous shortcomings, and/or fail to provide an instrument that is designed for optimal resonance and superior sound quality.
For example, some previously known “unitary” stringed instruments are actually use a separate neck that must be attached to a unitary body, which defeats the benefits gained from unitary construction techniques. Other prior art unitary stringed instruments use a neck that is strengthened using internal assemblies that make the instrument very heavy and thus reduces the resonance of the instrument. Some previously known stringed instruments are fully unitary, but include rigid soundboards that are not suitable for acoustic stringed instruments.
Some prior art stringed instruments have attempted to combine the benefits of unitary construction and expanded sound chamber design. However, such “combination” designs fail to achieve an instrument that is easy to manufacture, structurally sound and highly resonant.
It is therefore apparent that an urgent need exists for improved stringed instruments that produces similar sounds as traditional wooden instruments, is easy to manufacture and maintain, less sensitive changes in temperature and humidity, shock and impact resistant, portable, cost effective, and have long life.